1873 90¢ Official Stamp
Printed By: Continental Bank Note Co.
Printing Method: Engraved
Official Mail stamps are genuine postage stamps, although they were never available at any post office. These unique stamps are called Officials because their use was strictly limited to government mail. Before 1873, government agencies had “franking” privileges. This meant that government mail could be sent free of postage as long as it bore an authorized signature on the envelope. As of July 1, 1873, “franking” privileges were discontinued and special official stamps were put into circulation for use on government mail.
Each department was issued its own set of stamps. Many of the designs were taken from the current series of regular postage stamps being printed at that time - the so-called “Bank Note Issues.” The department names were inscribed on the stamps instead of the usual “U.S. Postage” and each set was printed in its own distinct color. Only the Post Office Department had its own unique design - a numeral in an oval frame.
In 1884, the Officials were declared obsolete and were replaced with the “penalty” envelope. These envelopes were imprinted with an official emblem and carried a warning against unauthorized use by private individuals.